1. Technical Field
The present invention relates to a content data recording medium and a music content using apparatus, and more particularly to a content data recording medium capable of preventing unauthorized use of music content and a music content using apparatus capable of preventing unauthorized use of music content stored on the content data recording medium.
2. Background Art
Various approaches to protecting the copyright of music content have been conventionally proposed, which disable use of music content other than those purchased in an authorized manner. For example, there is a technique for preventing illegal use of music content by embedding in the music content a license ID(s) representing electronic music instruments licensed to use the music content. Such a technique is disclosed for example in Patent Document 1.
Patent document 1 is Japanese patent laid-open application No. 2003-271766.
There is a case where license information for preventing unauthorized use of music content is included in a header chunk of the music content. In this case, it is considered that the data could be tampered, for example, by acquiring the header chunk of a music content purchased in an authorized manner and combining the header chunk with a data part of another music content which is intended to use in an unauthorized manner. When the data is tampered in this manner, conventional methods of preventing unauthorized use may inadvertently allow the unauthorized use of the music content since the header chunk of the tampered music content contains the license information.